1. Field of the Invention
The invention relates to the use of luteinizing hormone-releasing hormone antagonists (LHRH antagonists) in intrauterine insemination.
2. Background Information
One of the ethical problems of more recent times is the increasing sterility and unwanted childlessness of many couples. With respect to the therapy of these fertility disorders, inter alia, the following treatment methods of artificial fertilization have been established:
1. Substitution therapy--applied in patients with hypogonadotropic amenorrhoea
2. Stimulation therapy--given to anovulatory patients with active, albeit deranged hypothalamic pituitary-ovarian axis
3. Regulation therapy--employed in women with polycystic ovary disease (PCOD)
4. Hyperstimulation therapy--used in in vitro fertilization (IVF), gamete intrafallopian transfer (GIFT), tubal embryo transfer (TET), intracytoplasmatic sperm injection (ICSI) and intrauterine insemination (IUI).
The present invention especially relates to the improvement of the method of artificial sperm cell transfar in the uterus, i.e. the ferrtilization by intrauterine insemination (IUI) mentioned under item 4.
For the methods under items 2 and 4, it is necessary to stimulate follicle growth, which is achieved by the administration of gonadotropins, e.g. human menopausal gonadotropin (HMG or hMG), follicle stimulating hormone (FSH), and luteinizing hormone (LH), with or without preliminary therapy with clomiphene. It has further proved that the risk of luteinization by a premature LH surge, which leads to unfavourable implantation conditions arid relatively low pregnancy rates, can be decreased by complete suppression of the endogenous gonadotropins using gonadotropin releasing hormone (GnRH) agonists (Garcia et al. , 1984; Navot et al. , 1991; Hoffmann e al. , 1993).
For the control of ovarian stimulation with subsequent induction of ovulation, with the aim of obtaining fertilizable egg cells, both recombinant FSH and HMG and FSH and HMG obtained from urine are employed.
In connection with IUI, it is also desirable to control follicle growth and to specifically trigger ovulation.
The statements in the specialist literature about the therapeutic accompaniment of IUI, in particular using GnRH analogues, are mainly negative, such as, for example, the following:
1. IUI after ovarian stimulation with clomiphene may be important as the 1.sup.st choice of therapy, provided the male partner has a normal spermiogram (Hum. Reprod. 1997; July; 12(7):1458-1463). PA0 2. GnRH agonists/HMG stimulation, however, may be ineffective in routine IUI. Treatment with GnRH agonists with maximum suppression of the endogenous gonadotropins requires a relatively long treatment period (about 3 weeks) and leads to an increased consumption of HMG and is associated with side effects. PA0 3. Reports also exist which confirm that an increase in the pregnancy rate is not achieved by the use of GnRH agonists/HMG against HMG alone for IUI treatment in the case of unclarified infertility (Hum. Reprod. 1994 June 9(6)1043-1047. PA0 4. The cost differences of GnRH-a/HMG stimulation compared with clomiphene/HMG is indicated by Finnish authors an Eur. J. Obstet. Gynecol. Reprod. Biol. 1997 July 74: GnRH-a/HMG stimulation is not cost-effective in routine IUI therapy.
In a study by Diedrich et al. from 1994 Hum. Reprod. 1994 May; 9(5), the suppression of the undesired, premature LH surge by cetrorelix during ovarian stimulation with HMG and the on-time induction of ovulation was described in the context of a COS-ART study.
It was possible to shorten the length of the treatment period using this LHRH antagonist and the partial dose-dependent suppression of the endogenous gonadotropins additionally proved advantageous, since it was possible to reduce the consumption in comparison to the use of agonists of HMG.